Browser Activity Replay with Advanced Navigation

1. A computer program product for capturing and replaying activities conducted during a web browsing session, the computer program product comprising a non-transitory computer readable storage medium having program instructions embodied therewith, the program instructions executable by a processor to cause the processor to: receive activities conducted by a user via a browser application at a website, the activities occurring across multiple web pages and spanning multiple windows and multiple tabs across the multiple web pages during a single browsing session, wherein the activities include scrolling through a web page, selecting a tab, selecting a link on the web page, advancing to a different web page, returning to a previous web page, logging into the web site, logging out of the web site, entering data into a form, and creating a message, and wherein the receiving includes receiving messages including timestamps and load and unload events associated with the activities, each timestamp indicating when a corresponding activity occurred and the load and unload events indicating loading and unloading of the web pages; associate the activities with corresponding web pages at least in part by associating the activities spanning the multiple tabs with corresponding tabs; order the activities in chronological order for each of the web pages based on the corresponding timestamps; display user interface events corresponding to the ordered activities in a navigation list via the browser based interface, wherein the user interface events are selectable by an end user of the browser based interface, and wherein displaying the user interface events comprises displaying the load and unload events in chronological order of occurrence; receive a selection of a user interface event; and after receiving the selection of the user interface event: determine, by the browser based interface, a number of active windows at the time the activities were captured, the determining implemented by traversing upward in the navigation list and identifying all load messages that do not have matching unload messages; and create hypertext markup language (HTML) popup windows with iframes pointing to a most recent replay of each active window; and overlaying the popup windows on top of each other with an ordered index of the popup windows to indicate most recent activities on each active window.